I agree that fundamentally it's hardly new technology. AC Frequency Drives have been around in the industrial world for over 30 years now. 20+ years in the newer generations.
At my work I've used frequency drives on a type positve displacement blower as well as seen them applied on a oil free screw type air compressor which is simialr to a scroll. They worked well. The only issues were cooling airlfow on the compressor VFD (it was in a dusty environment and didn't get the filters changed) and correctly sizing hte drive to get adequate start-up torque on the blowers. So for example, a compressor that draws a 10A on constant run, might have a drive rated for 20A so it can handle the start-up current.
But for the HVAC mfg's it's still relatively new technology. Dirty power (common in residential) can be a problem. I wonder if Carrier has added line reactors or other power conditioning devices to prevent the issue on the Greenspeed.